I'm sorry but I just can't accept Powell's premise that Wilson is the "worst president" in American history in comparison to, among others, such presidents as Franklin Pierce, Andrew Johnson, U.S. Grant, Jimmy Carter, and of course Bill Clinton. By April 1917, Wilson really had no choice but to ask Congress to declare war on Germany in response to that country's gross provocations, including unrestricted U-boat warfare and the Zimmerman Telegram.
In fact, Wilson was a pacifist and did everything he could to keep America neutral. But the Kaiser gambled that he could beat the British, French, and the Russians before the U.S. could mobilize and transport the AEF to Europe and then tip the scales against Germany militarily, and he therefore forced Wilson's hand in the matter. Moreover, I think that it is patently unfair to solely blame Wilson for Hitler, Stalin, and World War II. Europe itself was entirely responsible for those evils, while America retreated into isolationism out of disgust at what was happening there in the aftermath of World War I.
["I'm sorry but I just can't accept Powell's premise that Wilson is the "worst president" in American history in comparison to, among others,...."]
You're right. I could probably do a pretty good job (but I wouldn't do it) in making a case that James Buchanan was the "worst" president in American History, e.g., his reaction to the 1857 Supreme Court Dred Scott Decision, letting the US sink into Civil War, ...etc. where the Civil War ultimately ended up costing more US lives than the collective number of losses of WWI and WWII.